I'm new to Mikrotik. I just bought the HAP AC2 and i'm on the configuration period. I have set this router as the main router of my home network which also connects to the internet via PPPoE through the ISP modem. I have also set up Pi-Hole as the local DNS. While i was trying to find a script for updating my DynDNS domain i found in the official wiki a page with a script for this purpose. https://wiki.mikrotik.com/wiki/Dynamic_ ... _No-IP_DNS. I tried the script several times with no success but after some debugging i noticed that firstly, the router couldn't resolve the domain (http://dynupdate.no-ip.com/) so i found out that the user must have set a DNS IP address under IP->DNS->Servers (maybe this must only be set up in the case you are using a local DNS as i do) and the second one was that the $previousIP variable in the script it seemed that on each run didn't have the previous value. So i noticed here that the suggested permissions write, test, read wasn't enough for the global variable to be set. So i granted policy permissions also and now everything works.
If the $previousIP is not set then on each run the script will send an ip update request to the DynDNS server even when the ip has not be changed (this is only noticeable though the logs. Otherwise the user is not affected)
So these two are suggestions if you are interested to be added in your official wiki page.